Jack



Patented .lunezs', 193s.

1 JACK a I i I Arthur Dickerson, Salt Lake city, ff 1 f Application' May 19, 1936, Serial No. s 0,4s3 I scleims. (oust-12 e l vI y invention relates to, jacks and has for its object to provide a new and efficientjack for lifting the newer types'of, automobiles which have so much fender extending at the rear end that it is impossible to get the ordinary jack under the axle for raising the wheel when it isdesired to change a tire. i

A further object is to provide a jack whichwill be strong and sturdy and one which will be made ,to meet all requirements for short or great lifts.

f A still further object is to provide a jack which will be compact in constructionand which will be of the screw. type [having double reverse threaded spindle'with a central support raising .withthe screw andwhich jack will lift iromabout four and. one half inches to about eighteen inches in height. I 'A stillfurther object is to provide a jack which will be made of a small enough screw to have v suflicient strength to raise all passenger auto- 'mobiles but which will also have sufiicient purchase to allow itto run freely thus, providing a jack which will be. easily operated and which will raise a car. quickly to any desired height at the same time eliminating the unnecessary raising of the entire body as is now done. with bumper jacks as this jack may be slid in-under the car without any trouble and is adaptable to lie/used directly on the axleof the car. 1

These objects Iaccomplish with the. device i1- lustratedin the accompanying drawingin which similar numerals and letters of reference indi- '.cate like parts throughout the several views and as describedin the specification forming a part of this application andpointed'out in the appended claims. 7

Inthe. drawing in which .I have shown my device,

Figure 1 is a side elevation of the jack in its lowered position. Figure'2 is an end View of Figure 1.

Figure 3 is a vertical section of the Jack taken at one side of the center line sectioning only the holding rivets or bolts and showing the inside of the exception that one is threaded internally op- Utahg to sea the two sides of the j ck M meny of I the twosides I and 2 which have the'portion between the two feet 3 and4 formed into twoop- I .posed arcs joined together at the middle, I provide adepending guide 5. Thisguide 5 on' each s 1 side is provided with an inwardly extended guide rib 6.

These two spaced apart guide ribs 6 aid in'holding' the jack screw Cin its proper position and at the same time hold the'central guide por ftion of the screw in proper position and the screw 10 in alignment and providing a vertical track in which thisguide rides. f The guide will be described later in this specification. 1

' Extending upwardly. and inwardly, continually raising as they near (the-center of the jack I pro- ,vide two spaced' apart'arc' shapedraces l and 8, each side being. identical in .curve and form. These two arcs provide part of the raising device essential to the complete and'satisfactory operation of this jack. The ends of the two arc- 2 0 shaped races 1 and 8 are turned upor curved slightly upward at their lower ends to permit pthe lifting platform-to be lowered to a greater degree than would be possible were this not so.

. v'I'h'e two sides l and 2 are held together by three rivets orholding bolts 10 and .H, which 02' with the section CI to fit into the internally k threaded nut 18 andthe section C2 tofit into .the threaded nut l 9-and the two vthreads reversed to-each other, one being a-right hand thread and the other being a left hand thread.

The nuts [8 and I!) are identical in form with posite to the other and each nut is provided with y a stub shaft 20 extending a short distance on one side and a like stub shaft 2| extending from the opposite side thus. providing opposed stub shafts on each nut and these stub shafts carry rollers 22, said rollers to operate in the two arcs l and 8 to aid in raising the jack platform D. The jack platform D is curved slightly on'the top side to fit it to the' axle of the automobile, This platform D is made with'a depending central boss in which there is a-transverse slot 3| and in which slot the sliding rivet is operated. The other end of this boss has a rivet 29 therethrough and on these two rivets the coacting arms 23 and 24 operate and are pivoted. These four arms 23 on one side and 24 on the opposite side are carried on the shafts 2| and 20 of the nuts l8 and I9 and the arms acting in pairs are crossed over and the arms or levers 23 fit onto the rivets 30 and the arms or levers 24 fit onto the rivet 29 and these four arms are each pivoted together into separate pairs one pair on each side of the screw and one pair is secured pivotally together by the rivet 21 and the other pair is secured together by the rivet 28, thus providing coacting equalaction pairs of arms orlevers acting from each side of the nuts I8 and 19 to raise and lower the foot or platform D. 1

Medially on the screw S there is a guide member of larger diameters than the rest of the screw" with the two ends l5 and I6 equal and with a central groove l1 therein, this groove operating .on the spaced apart guide ribs 6.1

end threaded, one with right hand threads, and

the other with left hand threads, said screw operating said threaded nuts; a guide medially on said screw carrying a central groove operating on said guide ribs; means to rotate said screw from one .end thereof; coacting levers mounted with their lower ends on the stub shafts of said. nuts and made in pairs with each pair on a side riveted pivotally together near the top ends thereof; and a lifting platform mounted pivotally to like levers of the pairs of levers, with the other like levers slidably mounted in a slot in said platform, said platform to be raised or lowered by the rotation of said screw. 1

2. In a jack, the combination of a platform on which the. load is carried; two pairs of coacting pivoted levers mounted to said platform; a vreversely threaded screw, opposed threaded screw nuts in which said screw is operated with the lower ends of said levers connected pivotally to said nuts; and a base'for said jack made of opposed identical sides having races on the inner sides thereof ascending toward the middle of'said base to raise andlower said nuts andlevers when the screw is rotated.

3. In a lifting jack, theecombination, of a lifting platform having a slot longitudinally and transversely along the bottom side thereof; two pairs of coacting levers one lever of each pair pivoted to the lowerside of; said platform and the other pair pivoted to a pivot pin carried in said slot; a base for said jack having are shaped races formed therein, ascending toward the medial portion thereof; rollers carried in said races; internally threaded nuts carrying stub shafts on each side thereof on which shafts the lower ends 'of said pairs of levers are pivoted andon which said rollers are mounted; and a double oppositely threaded screw carried in said nuts to be manually rotated to actuate .said rollers in said races drawing-thelevers toward each other to raise the lifting platform. 7

4. In a lifting jack, the combination of a base formed of two like formed castings secured together having each end formed into outwardly extended feet on which the jack rests; races formed on the inner sides of each casting said races being are shaped and-ascending toward the middle of the jack'with each outer end curved up slightly to allow the lifting platform to be lowereda greater degree; a central guide rib formed'on each; casting'extending inwardly toward each other; a double oppositely threaded jack screw having a central portion with a groove therein to ride on said central guide ribs; oppositely threaded .nuts carried on said screw each nut having stub shafts extended from two sides there.- of; rollers mounted on the ends of said -shafts and operating in'said races to roll up or down said races as the screw is rotated and the nuts 'moved in or out thereon; two sets of coacting levers mounted with their lower ends carriedlon said stub shafts and with their upper ends pivoted together near the top end thereof and a lifting platform mounted at the top of said levers with the pivot pin of one set of levers operating in a slot thereunder to'allow for raising said platform or lowering the same. V

5. In a jack, the combination of a lifting platform; two spaced apart pairs of'coacting pivoted levers mounted with one pair pivoted under said platform and the other pair. having a sliding mounting under said platform; a reversely threaded screw having a medial portion provided with an annular recess; opposed threaded nuts -AR'I'HUR DICKERSOLL 

